This play really irritates me by people who don't know it and try to push the fact the batter doesn't get first because the ball hit the dirt. If he doesn't get first then it has to be a dead ball and all runner return to base previously on.
Had a game one time where we had a runner on second and the ball clearly hit the batter after hitting the dirt - he jumped off the ground with both feet and the ball hit him in the foot and fell into fair territory.
The runner on second was stealing so he was at third about the time the ball hit the batter. Umpire never called time / dead ball. Runner starting limping towards first and the plate ump told him to come back - doesn't get first after ball hits ground. He allowed the runner to stay at third even after the defensive coach asked about it. Field ump never said a word.